11 research outputs found
The first two centuries of colonial agriculture in the cape colony: A historiographical reviewâ
A process supported by the utility BBPC for analysing Braun-Blanquet data on a personal computer
Many South African vegetation scientists use utilise the Braun-Blanquet methodology. The main aim of this paper is to describe an affordable, rapid and efficient process for analysing Braun-Blanquet phytosociological data sets on a personal computer. It describes a suite of utilities joining various phases and this makes the entire process possible
The plant communities and species richness of the <i>Alepidea longifolia- Monocymbium ceresiiforme</i> High-altitude Grassland of northern KwaZulu-Natal
As part of a vegetation survey of the grasslands of northern KwaZulu-Natal, this survey was conducted within the Alepidea longifolia-Monocymbium ceresiiforme grassland of high altitudes. Releves were compiled in 156 stratified random sample plots. The data set was classified using TWINSPAN. Subsequent refinement by Braun-Blanquet procedures produced 15 plant communities. Species richness was determined for each community. According to naturalness and species richness two communities were selected as being of conservation importance. An ordination algorithm (DECORANA) was also applied to describe the relationships between the vegetation units and the physical environment
The plant communities and species richness of the <i>Alepidea longifolia- Monocymbium ceresiiforme</i> High-altitude Grassland of northern KwaZulu-Natal
Major Vegetation Types of the Soutpansberg Conservancy and the Blouberg Nature Reserve, South Africa
The Major Megetation Types (MVT) and plant communities of the Soutpansberg Centre of Endemism are described in detail, with special reference to the Soutpansberg Conservancy and the Blouberg Nature Reserve. Phytosociological data from 442 sample plots were ordinated using a DEtrended CORrespondence ANAlysis (DECORANA) and classified using TWo-Way INdicator SPecies ANalysis (TWINSPAN). The resulting classification was further refined with table-sorting procedures based on the BraunâBlanquet floristicâsociological approach of vegetation classification using MEGATAB. Eight MVTâs were identified and described as Eragrostis lehmanniana var. lehmannianaâSclerocarya birrea subsp. caffra Blouberg Northern Plains Bushveld, Euclea divinorumâAcacia tortilis Blouberg Southern Plains Bushveld, Englerophytum magalismontanumâCombretum molle Blouberg Mountain Bushveld, Adansonia digitataâAcacia nigrescens Soutpansberg Arid Northern Bushveld, Catha edulisâFlueggia virosa Soutpansberg Moist Mountain Thickets, Diplorhynchus condylocarponâBurkea africana Soutpansberg Leached Sandveld, Rhus rigida var. rigidaâRhus magalismontanum subsp. coddii Soutpansberg Mistbelt Vegetation and Xymalos monosporaâRhus chirendensis Soutpansberg Forest Vegetation
Guidelines for phytosociological classifications and descriptions of vegetation in southern Africa
An overview of the vegetation of the VredeâMemelâWarden area, north-eastern Orange Free State
Classification and description of the vegetation in the Spitskop area in the proposed Highveld National Park, North West Province, South Africa
Evaluating herbivore management outcomes and associated vegetation impacts
African savannas are characterised by temporal and spatial fluxes that are linked to fluxes in herbivore populations and vegetation structure and composition. We need to be concerned about these fluxes only when management actions cause the system to shift towards a less desired state. Large herbivores are a key attribute of African savannas and are important for tourism and biodiversity. Large protected areas such as the Kruger National Park (KNP) manage for high biodiversity as the desired state, whilst private protected areas, such as those adjacent to the KNP, generally manage for high income. Biodiversity, sustainability and economic indicators are thus required to flag thresholds of potential concern (TPCs) that may result in a particular set of objectives not being achieved. In large conservation areas such as the KNP, vegetation changes that result from herbivore impact, or lack thereof, affect biodiversity and TPCs are used to indicate unacceptable change leading to a possible loss of biodiversity; in private protected areas the loss of large herbivores is seen as an important indicator of economic loss. Therefore, the first-level indicators aim to evaluate the forage available to sustain grazers without deleteriously affecting the vegetation composition, structure and basal cover. Various approaches to monitoring for these indicators were considered and the importance of the selection of sites that are representative of the intensity of herbivore use is emphasised. The most crucial step in the adaptive management process is the feedback of information to inform management decisions and enable learning. Feedback loops tend to be more efficient where the organisationâs vision is focused on, for example, economic gain, than in larger protected areas, such as the KNP, where the vision to conserve biodiversity is broader and more complex.
Conservation implications: In rangeland, optimising herbivore numbers to achieve the management objectives without causing unacceptable or irreversible change in the vegetation is challenging. This manuscript explores different avenues to evaluate herbivore impact and the outcomes of management approaches that may affect vegetation